Postby km1125 » August 9th, 2024, 5:01 pm
The fridge may be an AC/DC fridge and just not have a dedicated AC breaker.
But you need to think of ALL the DC loads that you could be running when you would be on dockside power. You have the potable water pump, blowers, head exhaust fans, bilge pumps, electric heads, radios (marine), chart plotter(s), USB outlets for phone chargers or other USB-powered stuff, "mood" lighting, underwater lights, CO alarms, fume alarms, tank monitor systems, etc. Not all that stuff runs all the time, but just bursts of higher-amperage stuff like the potable water pump will exceed the charger output then take a lot longer for a small charger to replace the charge.
Just my opinion, but I'd be thinking 30-40A would be the smallest I'd consider on that size boat. Others can weigh in with their experience.
I've had boat neighbors leave things on inadvertently after they've left the boat for the weekend. Something like a bilge blower would have drained their battery dead if they only had a 5A charger, but if they had a larger charger the blower would still be running when they came back the next weekend.